chrono::ChLoadBodyBody Class Reference

Description

Base class for wrench loads (a force + a torque) acting between two bodies.

See children classes for concrete implementations.

#include <ChLoadsBody.h>

Inheritance diagram for chrono::ChLoadBodyBody:

Collaboration diagram for chrono::ChLoadBodyBody:

Public Member Functions
	ChLoadBodyBody (std::shared_ptr< ChBody > bodyA, std::shared_ptr< ChBody > bodyB, const ChFrame<> &abs_application)
virtual void	ComputeBodyBodyForceTorque (const ChFrameMoving<> &rel_AB, ChVector<> &loc_force, ChVector<> &loc_torque)=0
	Compute the force between the two bodies, in local reference loc_application_B, given rel_AB, i.e. More...
ChVector	GetForce () const
	For diagnosis purposes, this can return the actual last computed value of the applied force, expressed in coordinate system of loc_application_B, assumed applied to body B.
ChVector	GetTorque () const
	For diagnosis purposes, this can return the actual last computed value of the applied torque, expressed in coordinate system of loc_application_B, assumed applied to body B.
void	SetApplicationFrameA (const ChFrame<> &mpA)
	Set the application frame of bushing on bodyA.
ChFrame	GetApplicationFrameA () const
void	SetApplicationFrameB (const ChFrame<> &mpB)
	Set the application frame of bushing on bodyB.
ChFrame	GetApplicationFrameB () const
ChFrameMoving	GetAbsoluteFrameA () const
	Get absolute coordinate of frame A (last computed)
ChFrameMoving	GetAbsoluteFrameB () const
	Get absolute coordinate of frame B (last computed)
std::shared_ptr< ChBody >	GetBodyA () const
std::shared_ptr< ChBody >	GetBodyB () const
Public Member Functions inherited from chrono::ChLoadCustomMultiple
	ChLoadCustomMultiple (std::vector< std::shared_ptr< ChLoadable >> &mloadables)
	ChLoadCustomMultiple (std::shared_ptr< ChLoadable > mloadableA, std::shared_ptr< ChLoadable > mloadableB)
	ChLoadCustomMultiple (std::shared_ptr< ChLoadable > mloadableA, std::shared_ptr< ChLoadable > mloadableB, std::shared_ptr< ChLoadable > mloadableC)
virtual int	LoadGet_ndof_x () override
	Gets the number of DOFs affected by this load (position part)
virtual int	LoadGet_ndof_w () override
	Gets the number of DOFs affected by this load (speed part)
virtual void	LoadGetStateBlock_x (ChState &mD) override
	Gets all the current DOFs packed in a single vector (position part)
virtual void	LoadGetStateBlock_w (ChStateDelta &mD) override
	Gets all the current DOFs packed in a single vector (speed part)
virtual void	LoadStateIncrement (const ChState &x, const ChStateDelta &dw, ChState &x_new) override
	Increment a packed state (ex. More...
virtual int	LoadGet_field_ncoords () override
	Number of coordinates in the interpolated field, ex=3 for a tetrahedron finite element or a cable, = 1 for a thermal problem, etc.
virtual void	ComputeJacobian (ChState *state_x, ChStateDelta *state_w, ChMatrixRef mK, ChMatrixRef mR, ChMatrixRef mM) override
	Compute jacobians (default fallback). More...
virtual void	LoadIntLoadResidual_F (ChVectorDynamic<> &R, double c) override
	Adds the internal loads Q (pasted at global nodes offsets) into a global vector R, multiplied by a scaling factor c, as R += forces * c.
virtual void	LoadIntLoadResidual_Mv (ChVectorDynamic<> &R, const ChVectorDynamic<> &w, double c) override
	Default fallback: compute jacobians via ComputeJacobian(), then use M=-dQ/da to do R += c*M*w. More...
virtual void	CreateJacobianMatrices () override
	Create the jacobian loads if needed, and also set the ChVariables referenced by the sparse KRM block.
virtual ChVectorDynamic &	GetQ ()
	Access the generalized load vector Q.
Public Member Functions inherited from chrono::ChLoadBase
ChLoadJacobians *	GetJacobians ()
	Access the jacobians (if any, i.e. if this is a stiff load)
virtual void	Update (double time)
	Update: this is called at least at each time step. More...
virtual bool	IsStiff ()=0
	Report if this is load is stiff. More...
virtual void	InjectKRMmatrices (ChSystemDescriptor &mdescriptor)
	Tell to a system descriptor that there are item(s) of type ChKblock in this object (for further passing it to a solver)
virtual void	KRMmatricesLoad (double Kfactor, double Rfactor, double Mfactor)
	Adds the current stiffness K and damping R and mass M matrices in encapsulated ChKblock item(s), if any. More...
Public Member Functions inherited from chrono::ChObj
	ChObj (const ChObj &other)
virtual ChObj *	Clone () const =0
	"Virtual" copy constructor. More...
int	GetIdentifier () const
	Gets the numerical identifier of the object.
void	SetIdentifier (int id)
	Sets the numerical identifier of the object.
double	GetChTime () const
	Gets the simulation time of this object.
void	SetChTime (double m_time)
	Sets the simulation time of this object.
const char *	GetName () const
	Gets the name of the object as C Ascii null-terminated string -for reading only!
void	SetName (const char myname[])
	Sets the name of this object, as ascii string.
std::string	GetNameString () const
	Gets the name of the object as C Ascii null-terminated string.
void	SetNameString (const std::string &myname)
	Sets the name of this object, as std::string.
void	MFlagsSetAllOFF (int &mflag)
void	MFlagsSetAllON (int &mflag)
void	MFlagSetON (int &mflag, int mask)
void	MFlagSetOFF (int &mflag, int mask)
int	MFlagGet (int &mflag, int mask)
virtual void	ArchiveOUT (ChArchiveOut &marchive)
	Method to allow serialization of transient data to archives.
virtual void	ArchiveIN (ChArchiveIn &marchive)
	Method to allow de-serialization of transient data from archives.
virtual std::string &	ArchiveContainerName ()

Protected Member Functions
virtual void	ComputeQ (ChState *state_x, ChStateDelta *state_w) override
	Compute Q, the generalized load. More...

Protected Attributes
ChFrame	loc_application_A
	application point on body A (local)
ChFrame	loc_application_B
	application point on body B (local)
ChVector	locB_force
	store computed values here
ChVector	locB_torque
	store computed values here
ChFrameMoving	frame_Aw
	for results
ChFrameMoving	frame_Bw
	for results
Protected Attributes inherited from chrono::ChLoadBase
ChLoadJacobians *	jacobians
Protected Attributes inherited from chrono::ChObj
double	ChTime
	the time of simulation for the object

Additional Inherited Members
Public Attributes inherited from chrono::ChLoadCustomMultiple
std::vector< std::shared_ptr< ChLoadable > >	loadables
ChVectorDynamic	load_Q

Constructor & Destructor Documentation

ChLoadBodyBody()

chrono::ChLoadBodyBody::ChLoadBodyBody	(	std::shared_ptr< ChBody >	bodyA,
		std::shared_ptr< ChBody >	bodyB,
		const ChFrame<> &	abs_application
	)

Parameters

bodyA	body A
bodyB	body B
abs_application	location of load element (in abs. coordinates)

Member Function Documentation

ComputeBodyBodyForceTorque()

virtual void chrono::ChLoadBodyBody::ComputeBodyBodyForceTorque ( const ChFrameMoving<> &  rel_AB, ChVector<> &  loc_force, ChVector<> &  loc_torque  )

pure virtual

Compute the force between the two bodies, in local reference loc_application_B, given rel_AB, i.e.

the position and speed of loc_application_A respect to loc_application_B. Force is assumed applied to loc_application_B of body B, and its opposite reaction to A. Inherited classes MUST IMPLEMENT THIS.

Implemented in chrono::ChLoadBodyBodyBushingGeneric, chrono::ChLoadBodyBodyBushingMate, chrono::ChLoadBodyBodyBushingPlastic, and chrono::ChLoadBodyBodyBushingSpherical.

ComputeQ()

void chrono::ChLoadBodyBody::ComputeQ ( ChState *  state_x, ChStateDelta *  state_w  )

overrideprotectedvirtual

Compute Q, the generalized load.

It calls ComputeBodyBodyForceTorque, so in children classes you do not need to implement it. Called automatically at each Update().

Parameters

state_x	state position to evaluate Q
state_w	state speed to evaluate Q

Implements chrono::ChLoadBase.

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The documentation for this class was generated from the following files:

• /builds/uwsbel/chrono/src/chrono/physics/ChLoadsBody.h
• /builds/uwsbel/chrono/src/chrono/physics/ChLoadsBody.cpp